New triarylmethane dyestuff



Patented Nov. 24, 193 1 UNITED-STATES.

BERTHOLZD WENK AND HERMANN 's'rorTER,

RHINE, GERMANmnssIeNoRs 'ro GENERAL} 'N. Y., A CORPORATION OIE DELAWARE 1 NEW TRI RYL rniinn nxnstrurii in Drawing. Application filed rebruar ie, 1927, Serial Nb 163,824, 'en ii't rman ira'r c1f12 i92af The present invention relates to processes for the production of triarylmethane dyestuffs.

It is known that one may obtain triarylmethane dyestuffs by condensing hydroxydiaryl-methanes with aromatic hydroxy-compounds by means of nitrosyl-sulphuric acid in strong sulphuric acid.

The present invention is based upon the discovery that one can obtain valuable'triaryl-methane dyestuffs in a much simpler i stance, 47 5 parts by weight of a"17% solution manner by oxidizing hydroxy-diaryl-meth;

anes, hydroxy-diaryl-hydrols or other para-' methylated aromatic hydroxy-compoundsto gether with aromatic hydroxy-compounds in alkaline solution. 7 r f Example 1.'3l;6 parts by weight'of methylene-di-ortho-cresotinic acid and 34.8 parts by weight of sodium-2+hydroxynaphthalene-. 3.6-disulfonate 'are rdissolve'd with, for inof sodium hydroxide, and, in order to obtain a better transmissionof oxygen, the solution is intensively mixedwith-air at C. in the presence of 1 part by weight of coppersulv phate or another similar'metal compound known as anoxidation catalyst, such,-for example, as ferric sulfate, ferric chloride,

copper chloride and the like. I The. stirring is continued until no more dyestufl is formed,

after which the resulting dyestufl is isolated in the usual manner. It is, in its dry powdered form, a brown powder soluble in water with a reddish coloration which changes into a blue when sodium-hydroxide is added to this solution. It dyes wool, with afterchroming, a reddish blue shade. It has most probably the formula: I i

HOOC I Ewample a 15.2 eas by weight a p cresotinic acid and-30.4 parts by weight of P p e sha e-- 3.6' disulpho'nic acidin Example 1', )Z-rlapl thol and its derivatives (suehas, forflexample, the corresponding sulphonic andcarboxylic acids), and also "corresponding derivatives 'ofthe l-naphthols and poly-hydroxy-naph- I their carboxylic acids, may be used.

o-eresotinic acid are dissolvedfin 475 partsby weight of 17 %'solution of sodium'hydroxide and the reaction mixture oxidized as in i Example 1. -Theresultingidyestufl', awed-g dish brown powderysoliible inian aqueous 55. solution of caustic sodawith a red'coloration, after-chromated upon wool, yields a reddish Itihasmost 'pr-obably the formula I 5 VI-+7- Insteadof; methylene-discscresotinic iacidi :droxysdiaryl-methanes, yas, for 1 example,

imethylene-di-o-cresol, methylene-dirsalicylic 7' V 4-hydroxy-5 -carboxy-diphenyl-methane having most probablythe-formula x 111901 V U I z shN it 7 I coon i ll' d q r5 ib yrhehy me m ae i' 'h i hydrols which'correspond thereto. i

In placeof the sodiumsaltof2 naphthol i 'thalenes, phenols, poly-hydroxybenzols or In Example; 2, p-cresol foraderivative 7 i 7 thereof can be used instead of p-cresotinic acid. I In place of o-cresotinic; acidin 'E xample 2, other aromatic hydroxy-acids 'or' phenol, cresol or their 'substitution products',

"re as, for instance, i4 di+ethylaminos3smethyl= 10 scribed 'proced'ui eai. e., condensationof an hydroxy diaryl-lnethane compound with an aromatic hydroxy compound in ealkaline'so V lution, but'alsjoztnequivalent procedure such q es for example the b ui-ldingup of a diaryl 'methane compound'during the reaction, for d y' T example, as is efiectedwhen one condenses a compound ofithe type formula V 5 Yduction of the cornesponding tr iarylmethane i J V a hydroxy-diarylinetha ne compound With an 1 V wherein the aryl nucleusmay be further sub stituted*,]iwvith two fnole'cula'r proportions of an aromatic hydroxy compound, tothe'prodyestuff; I

V; /We claim: V c V 1; ProcessfOn-theproduction of a-tria-ryli f methane dyestu'fi' which comprises-condensing aromatic hydroXy compound men-alkaline sulfonate of the following formula:

e V: In-testimony whereof; 'we cafliiz'our signa-v,

' 1103s sofa 50in: the p esence offcoppen sulfate ut actexn j perature ofeboutf9r0 Ci While mi i g it v p aura YBEBTHOLDJ Y e "LHEBMANN.JSTQTTER 

